From 95833c83f3b812c78e48db4eaa19f6c74958470b Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 11 Jan 2006 22:44:36 +0100 Subject: [PATCH] x86_64: Add idle notifiers This adds a new notifier chain that is called with IDLE_START when a CPU goes idle and IDLE_END when it goes out of idle. The context can be idle thread or interrupt context. Since we cannot rely on MONITOR/MWAIT existing the idle end check currently has to be done in all interrupt handlers. They were originally inspired by the similar s390 implementation. They have a variety of applications: - They will be needed for CONFIG_NO_IDLE_HZ - They can be used for oprofile to fix up the missing time in idle when performance counters don't tick. - They can be used for better C state management in ACPI - They could be used for microstate accounting. This is just infrastructure so far, no users. Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- include/asm-x86_64/idle.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) create mode 100644 include/asm-x86_64/idle.h (limited to 'include') diff --git a/include/asm-x86_64/idle.h b/include/asm-x86_64/idle.h new file mode 100644 index 00000000000..6bd47dcf206 --- /dev/null +++ b/include/asm-x86_64/idle.h @@ -0,0 +1,14 @@ +#ifndef _ASM_X86_64_IDLE_H +#define _ASM_X86_64_IDLE_H 1 + +#define IDLE_START 1 +#define IDLE_END 2 + +struct notifier_block; +void idle_notifier_register(struct notifier_block *n); +void idle_notifier_unregister(struct notifier_block *n); + +void enter_idle(void); +void exit_idle(void); + +#endif -- cgit v1.2.3